Cooling system for rotary mechanisms



May 28, 1963 HANNS-DIETER PASCHKE 3,091,386

COOLING SYSTEM FOR ROTARY MECHANISMS Filed April 13, 1960 5 Sheets-Sheet l 2 F I G I- r2 I 22 INVENTOR. HAN NS-D| ETER PASCH KE ATTaRA/A'YJ May 28, 1963 HANNS-DIETER PASCHKE 3,091,386

COOLING SYSTEM FOR ROTARY MECHANISMS Filed April 13, 196 0 5 Sheets-Sheet 2 FIG- 2- I l G- 4.

INVENTOR. HAN NS- D l ETER PASCH KE May 28, 1963 HANNS-DIETER PASCHKE 3,

COOLING SYSTEM FOR ROTARY MECHANISMS Filed April 15, 1960 5 Sheets-Sheet 3 INVENTOR. HAN NS-Dl ETER PASCl-l KE ATTORNEYS May 28, 1963 Filed April 1:5, 1960 HANNS-DIETER PASCHKE COOLING SYSTEM FOR ROTARY MECHANISMS 5 Sheets-Sheet 4 6 INVENTOR. HAN NS-Dl ETE R PASCHKE 6 ATTORNEYS May 28, 1963 HANNS-DIETER PASCHKE COOLING SYSTEM FOR ROTARY MECHANISMS Filed April 15, 1960 5 Sheets-Sheet 5 INVENTOR. HAN N S- DI ETER PASCH KE BY W, Zia-a Z;

A TTaR/VE vs United States Patent U 3,091,386 COOLING SYSTEM FOR ROTARY MECHANlSit ifl Harms-Dieter Paschke, Neckarsulm II, Germany, assignor to NSU Motorenwerke Aktiengesellschaft, Neckarsulm, rma and W el G-m-b-H, nd nd e Germany Filed Apr. 13, 1960 Ser. No. 21,989 Claims priority, application Germany Apr. 23, 1959 7 Claims. (Cl. 230-145) The present invention relates to an improved cooling system for rotary mechanisms, and more particularly to a cooling system for the rotors of such mechanisms which can be combined in part with the lubricating system of the mechanism.

Although this invention is applicable to and useful in almost any type of rotary mechanism which presents a cooling requirement, such as combustion engines, fluid motors, fluid pumps, compressors, and the like, it is particularly useful in rotating combustion engines. To simplify and clarify the explanation of the invention the description which follows will, .for the most part, be restricted to the use of the invention in a rotating combustion engine. It will be apparent from the description, however, that with slight modifications which would be obvious to a person skilled in the art, the invention is equally applicable to other types of rotary mechanisms.

The present invention is particularly useful in rotating combustion engines of the type which comprise an outer body having an axis, axially-spaced end walls, and a peripheral wall interconnecting the end walls; the inner surfaces of the peripheral wall and end walls form a cavity, and an inner body or rotor is mounted within the cavity between its end walls. The inner surface of the peripheral wall is preferably parallel to the axis of the cavity and, as viewed in a plane transverse to this axis, the inner surface preferably has a multi-lobed profile which approximates an epitrochoid. The axis of the rotor is parallel to, but spaced from, the axis of the cavity of the outer body, and the rotor has axially-spaced end faces disposed adjacent to the end walls of the outer body and a plurality of circumferentially-spaced apex portions. The rotor is rotatable relative to the outer body such that the apex portions substantially continuously engage the inner surface of the peripheral wall in sliding, gas-sealing contact to form between the outer surface of the rotor and the inner surface of the outer body a plurality of working chambers which vary in volume during engine operation, as a result of relative rotation between the rotor and the outer body.

Such engines also include an intake passage for administering a fuel-air mixture to the chambers, an exhaust port for the chambers, and suitable ignition means so that during engine operation the working chambers of the engine undergo a cycle of operation which includes the four phases of intake, compression, expansion, and exhaust. This cycle of operation is achieved as a result of the relative rotation of the inner rotor and outer body, and for this purpose both the inner rotor and outer body may rotate at different speeds, but preferably the inner rotor rotates while the outer body is stationary.

For efiicient operation of the engine, its working chambers should be sealed, and therefore an effective seal is provided between each. rotor apex portion and the inner surface of the peripheral wall of the outer body, as well as between the end faces of the inner rotor and the inner surface of the end walls of the outer body.

One embodiment of the rotating combustion engine which has been successfully used in practice is an engine in which the multi-lobed inner surface of the outer ree body approximates the geometric form of an epitrochoid. The general shape of the inner rotor is determined by approaching the maximum size rotor which the inner surface of the outer body can accommodate without creating interference contact between the outer surface of the rotor and the inner surface of the outer body. It is apparent that the theoretical maximum size rotor will also yield the theoretical maximum possible compression ratio for the engine. In this embodiment the shape of the rotor is polygonal or has the general configuration of a polygon with externally or internally curved arcuate sides, the apex portions of the rotor being in continuous contact with the inner Wall or surface of the stator.

For purposes of illustration the following description Will be related to the present preferred embodiment of the engine in which the inner surface of the outer body defines a two-lobed epitrochoid, and the rotor or inner body has three apex portions and is generally triangular in cross-section but has curved or arcuate sides. It is not intended that the invention be limited, however, to the form in which the inner surface of the outer body approximates a two-lobed epitrochoid and the inner body or rotor has only three apex portions. In other embodiments of the invention the inner surface of the outer body may approximate an epitrochoid having one less lobe than the rotor or inner body has apex portions.

In this description of the invention the geometric form of the contour of the rotor which will yield the theoretical maximum compression ratio and still be theoretically free to rotate will be termed the inner envelope of the approximate epitrochoidal inner surface of the outer body, or, for brevity, the inner envelope.

In the one embodiment of the invention, an end face of the rotor is provided with an internally-toothed ring gear which is concentric with the bearing bore of the rotor and of approximately the same diameter as the bearing bore. A fixed or stationary externally-toothed or pinion gear of smaller diameter than the rotor gear is adapted to fit into and mesh with the teeth of the rotor gear as the rotor makes its revolutions during operation of the engine.

It is a primary object of the present invention to provide means for efficiently circulating a cooling fluid through the rotor without the necessity for a pump.

It is another object of the instant invention to provide a cooling system for the rotor, which will permit the use of one fluid for both cooling of the rotor and lubrication of the mechanism.

Another object of the present invention is to provide means for cooling both the inner rotor and the outer body in, the form or embodiment of the invention in which both the inner rotor and outer body are rotary and rotate relative to each other.

Another object of the present invention is to provide a cooling system for the rotor, which Will permit the cooling fluid to freely circulate in the rotor and at the same time prevent its passage from the rotor into the working chambers of the engine.

A further object of the instant invention is to provide a cooling system for the rotor which will automatically maintain a reservoir of cooling fluid in the rotor at a substantially unvarying volume.

A still further object of the present invention is to provide a return passage for the cooling fluid from the rotor that is radially outward from the inner rotor bearings, and radially outward from the gearing, so that neither the bearings nor the gearing run immersed in the cooling fluid and churning and sloshing of the fluid is avoided.

In accordance with the instant invention, an internal cavity is provided in the rotor through which the cooling fluid flows. 1e cooling fluid or liquid is introduced into the cavity, preferably under pressure, through appropriate passages; and preferably these supply passages comprise a central bore in the crankshaft, a radial passage in the eccentric, and appropriate orifices and passages leading to the main cavity of the rotor itself. The return passage of the cooling liquid from the rotor cavity is eifected by one or more stationary conduit means or passages which communicate at their radial outer ends for at least a part of a revolution of the rotor with the cavity at a point or points which are radially beyond the bearings and gearing of the rotor. The radial inner ends of the exit passages extend in an axial direction beyond an end face of the rotor and beyond the adjacent end wall of the stationary or rotary outer body.

The cooling liquid forms a fluid ring around the outer periphery or surface of the rotor cavity, under the influence of centrifugal forces as the rotor rotates. If the radially extending passages or conduit means dip their outer ends into the cooling liquid, the cooling liquid will be pumped by centrifugally generated pressure through the passage or conduit means. This may occur intermittently in any given passage when the peripheral end of the passage is intermittently immersed in the cooling liquid by narrowing of the distance between the radially outer surface of the rotor cavity and the ends of the passages, caused by eccentricity between the center from which the passages radiate and the axis of the rotor cavity. However, if the ring of liquid is deep enough to immerse the ends of all passages, pumping will be continuous through all. The conduit means, therefore, acts as a pump and determines the liquid level of the cooling fluid within the rotor in such a Way that escape or passage of the cooling liquid through the openings in the end faces of the rotor which accommodate the eccentric is prevented and passage of the fluid from these openings along the end walls of the outer body and into the working chambers of the engine is also prevented. These conduit means accordingly obviate the need for a complex or expensive cooling fluid sealing means between the end faces of the rotor and the end walls of the outer body.

Preferably the conduit means is in the form of a channel provided with a stationary disc, which extends or radiates into the cavity of the rotor. Advantageous results can be obtained by making the conduit means or passages of spiral shape; this construction favors the easy entrance of the cooling liquid into the conduit means and also increases the effectiveness of centrifugal pressure in pumping excess cooling fluid from the cavity, whether the peripheral ends of the passages are dipped intermittently into the cooling liquid by means of the narrowing action, or whether all passage ends are continuously immersed.

If the rotating combustion engine is in the form in which both the inner rotor and outer body rotate during operation of the engine, the problem of supplying a cooling liquid to the inner rotor and circulating it through this rotor becomes more complex. In this form or en bodiment of the invention the eccentric remains stationary or fixed while both the outer body and inner rotor rotate during operation, and the powershaft is connected to the outer body so that it is driven by rotation of the outer body. Passages or conduits within the stationary eccentric are used both for the supply and return of a cooling liquid to and from both the outer body and the inner rotor. Similarly to the earlier described form of the invention, the return passages extend radially outward into the cooling liquid cavity within the inner rotor, so that as soon as the radial depth of the cooling liquid in the fluid ring within the cavity is sufficient to immerse the outer end of the return passage, the centrifugal pressure on the liquid within the inner rotor will act to 4 force or pump the cooling liquid into the passage and out from the cavity. The centrifugal pumping action in the return passage thus acts to limit and determine the volume of cooling liquid within the inner rotor cavity. In this embodiment also, the return passage preferably communicates with the cooling liquid at a point radially beyond the rotor bearings and gearing so that neither the bearings nor the gearing will run immersed in the cooling liquid, and churning of the liquid is avoided. Further, the outer end of the return passage may be inclined to the direction of rotation of the liquid within the cavity, or preferably take a spiral shape, to enhance the pumping action and return flow of the cooling fluid.

Broadly described, the present invention includes means for efficiently circulating a cooling fluid through the rotor and maintaining a pro-established quantity of the fluid in the rotor without the need for an auxiliary pump, inlet means to conduct the fluid into the rotor, outlet means to withdraw the fluid from the rotor into the working chambers of the engine, and means to prevent immersion of the rotor bearings and gearing in the cooling fluid.

Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention, the objects and advantages being realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations, and improvements shown and described.

The accompaying drawings, which are incorporated in and constitute a part of this specification, illustrate one embodiment of the invention and, together with the description, serve to explain the principles of the invention.

In the accompanying drawings illustrating the mechanical aspects of the present invention, it is believed that the showing of the fundamental construction, functions, originality and advantages of the invention may be more easily understood when certain details of practical construction are omitted, where these details form no part of the claimable invention, are well-known to those skilled in the art, and could be incorporated in the present invention by any skilled workman. These details may consist of means for lubrication, such as oil cups, grooves, reservoirs, seals, wipers and O-rings; means for reduction of friction, such as, bushings, ball bearings, and roller bearings; means for sealing off various spaces or areas to confine fluid pressures to their functional locale, such as, packing, packing glands, O-rings, and gaskets; constructlonal details of fluid conducting means, such as, tube or pipe joints, unions, and elbows including supporting and securing means; and such other comparable means and devices that may be omitted for the sake of clarity.

Of the drawings:

FIG. 1 is a central vertical section taken along the line ll of FIG. 2 of the invention in which the outer body is stationary and the rotor and eccentric rotate during operation of the engine;

FIG. 2 is a plan view of the rotor mounted within the outer body and showing the rotor partially in vertical section taken along the lines 2-2 of FIG. 1;

FIG. 3 is a fragmentary central vertical section of an alternative embodiment of FIG. 1;

FIG. 4 is a section of the rotor in an alternative construction, showing the stationary disc with spiral-shaped return passages;

FIG. 5 is a central vertical section of an embodiment of the invention in which the eccentric is stationary and both the outer body and inner rotor rotate during operation of the engine;

FIG. 6 is a cross-section of a front elevation taken along the line 6-6 of PEG. 5.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory but; are not. restrictive of the invention.

Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated inthe accompanying drawing and in whichFIG. 2 shows a generally triangular rotor 10 having arcuate sides and eccentrically supported for rotation withinan outer body 12. In the illustrative embodiment shown in FIGS. 1 and 2, the outer body 12 is fixed or stationary.

As can be seen in FIG. 1, the stationary outer body 12-corn-prises two end walls 18 and-'20 and a peripheral Wall 22 interconnectingthe end walls 18 and 20. The outer body 12 is completedby the cover plates 19 and 21 which are secured to the end walls 18 and 20, respectively. The inner surface contour 24 of the peripheral-wall 22 isin this embodiment-preferably a two-lobed epitrochoid, which is mostclearly shown by FIG. 2. A crankshaft 26 is rotatably supported within the outer body 12 by means of conventional antiafriction bearings 28 and 30, and the axis of the crankshaft 26 is coincident with the axis 16 of the outer. body 12. Rigidly mounted on and forming an integral part of the crankshaft 26 is an eccentric 32 having an axis eccentric to and parallel to the crankshaft axis. This central axis of the eccentric 32 is coincident with the axis 14- of the rotor .10, and the rotor 10 is rotatably mounted on and supported by the eccentric 32 by means of a bearing34.

The outer contour of the rotor 149- has a shape which approaches the shape of the inner envelope of the approximate epitrochoidal contour of the inner surface 24 of the outer body 12. In the illustrative embodiment shown in FIG. 2, this gives the rotor 10 the general shape of a triangle with arcuate sides. The actualshape of the rotor 10 must always vbe somewhat smaller than the size of the inner envelope, since there must be no interference contact between the sides of the rotor 10 and the inner surface 24, and allowance must be made for production tolerances and operating clearances and deflections. As shown in FIG. 2, the rotor 10 includes three apex portions 38 which carry radially. movable sealing means 40 which are in substantially continuous sliding, gas-sealing contact with the inner surface 24 of the outer body 12, three variable volume working chambers 25 are formed between the outer peripheral surfaces 42 of the rotor 10 and the inner surface 24 of the outer body 12.

As shown in FIG. 2, an intake passage 44 for fresh fuel-air mixtures, an exhaust passage 46 for burnt gases, and a spark plug 48 for igniting a combustible mixture are provided within the peripheral wall 22 of the outer body 1 2. As the rotor ltl'rotates in the direction of the arrow (FIG. 2), fresh combustible gases are successively sucked in, compressed, ignited, expanded and then exhausted. A complete cycle of the engine thus takes place, and this cycle includes the four phases of intake, compressions, expansion and exhaust. These phases are directly comparable to the four strokes of a conventional internal. combustion piston engine.

As embodied, and as may be seen in FIG. 1, an internally toothed ring gear 50 is fixed to an end face of the rotor coaxial with an opening 52 in the rotor in said end face. A pinion or externally toothed gear 54 is rigidly attached to the end wall 18-ofthe outer body 12 by means of gear support 53- and is in mesh with the rotor gear 56. In the illustrative embodiment of the invention shown by FIG. 1 the ratio of the inter-meshing teeth between the rotor gear 50 and the end wall gear 54 is 3:2, so that for every revolution of the rotor 10 about its own axis the crankshaft 26 rotates three times in the same direction. Since the rotor 10 is journaled on the eccentric 32, the end faces of the rotor 10 are open at 52 and 56. and therotor gear 50 is arranged within one of these openings 27.

The rotor 1t! v is provided with a cavity 58-which is supplied with cooling fluid through a central bore 60 within the crankshaft 26 and a passage 62 extending radially to the periphery of the eccentric 32 and its bearing 34; the fluid flows from the end of the bearing into the cavity 58. For return conveyance and to aid in circulation of the cooling fluid a stationary disc 64- is arranged within the cavity 58 of the rotor 10. The disc 64 is continued by a tubular hub 66 which extends axially beyond the rotor and is fixed to the end wall 20 0f the outer body 12 Radially a depth such that the openings of some of the channels 68 dip into the fluid ring, by narrowing-of the distance between the radially outer surface of the rotor cavity and the ends of the passages, caused by eccentricity between the center from which the passages radiate and the axis of the rotor cavity, the cooling liquid will be conveyed by centrifugally generated pressure through these channels. The fluid will then flow under centrifugalpressure through the channel 64 into an annular chamber 7tl within the end wall 20 of the housing '12, through the bore '72 into a chamber 74- and will finally leave the engine through the outlet connection 75 to a cooling radiator (not shown). From the cooling radiator the now cooled fluid can be recirculated through the rotor and re-enter the engine at the central bore 60.

From the foregoing description it may beseen that the return passages 68 act as a pump to limit the quantity of cooling fluid within the inner rotor or rotor cavity 58 bypumping excess fluid out of the cavity through the passage.

Preferably, the disc 64'extends radially outward beyond the opening 56 in the end face 23 of rotor 10 in every position of the rotor, whereby the return passages 68 communicate with the cavity 58 at a point in the relative movement between rotor and outer body which is. always radially beyond the opening 56, the eccentric bearing 34, and the gears. 50 and'54 between rotor and outer body. As the return passages 68 prevent the radial depth of the cooling fluid in the fluid ring from increasing radially inward substantially beyond the radially outer ends 76 of these passages, the escape of coolingfluid through the openings 56and-52 andv along the end faces 21 and 2-3- ofthe rotor 10 to the working chambers is prevented. Also, with this arrangement neither the eccentric bearings 34 which support the rotor. nor the rotor gear- 50 and stationary gear 54:r.un immersed in the cooling fluid, and churning of the cooling fluid by these bearings and gears is thus prevented.

Also shown inFIG. l, but forming nopart of the pres.- ent invention, are two flywheels attached to the crankshaft 26, one on either, side of the rotor 10, and appropriately arranged cooling fluid passages within the outer body 12 for. cooling of the outer body.

FIG. 3 shows an alternative embodiment ofthe invention in which the external teeth 54' of the stationary externally toothed gear are carried by the tubular hub tube 66 of. the disc 64. Asin the embodiment shown in FIG.

1, these teeth 545 are in mesh with the internally toothed;

rotor gear 50, which in the embodiment of FIG. 3 is, of course, moved to the right-hand side of the. rotor. alternative embodiment depicted. in FIG. 3. simplifies. the over-all construction of the engine.

Advantageously, the outer ends ofthe return passages may be inclined into the-directionofrotation of the cooling fluid within the rotor and a circumferentially-spaced arrangement of a plurality of these return passages may be provided. A preferred means for achieving this advantageous feature of the invention is shown in FIG. 4'

in which a stationary disc 64 is shown incross-section,

This.

and this disc 64 corresponds to the disc 64 of FIG. 2. The return passages 61% in the disc 64 preferably radiate spirally outward in the direction opposed to rotor rotation, so that upon rotation of the rotor 11} in the direction of the arrow (FIG. 4) the cooling fluid which is revolving together with the rotor is removed more efliciently when the disc 64' clips into the cooling fluid. The spiral-shaped return passages facilitate entrance of the cooling fluid by a scooping action and enhance the pumping eifect of the centrifugally generated pressure in the fluid ring by tending to preserve the natural direction of flow of the fluid and thus reducing head losses in the passages. For simplification in manufacture, the disc 64 may be constructed of two parts; one part includes the preferably milled spiral grooves and the hub portion of the disc, and the other part is a planar disc which covers these grooves.

In FIGS. 5 and 6 an alternative embodiment of the engine is shown in central vertical section and cross-section views respectively. The rotary mechanism shown in FIGS. 5 and 6 is a form in which both the inner rotor and outer body are rotary in operation and in which the inner rotor is journaled on a stationary eccentric. In this embodiment of the invention the stationary eccentric is used to provide passages for the supply and return of a cooling fluid for circulation through the inner rotor and outer body of the rotary mechanism. These features are clearly shown in FIGS. 5 and 6.

Reference will now be made in detail to the embodiment of the invention illustrated in FIGS. 5 and 6. The parts of FIGS. 5 and 6 which correspond to parts of FIGS. 1 and 2 have been designated by these same reference numerals as in FIGS. 1 and 2 but with the prefix 1 or the amount 100 added; thus, the rotor 10 of FIGS. 1 and 2 becomes the rotor 110 of FIGS. 5 and 6.

In this alternative embodiment the outer body 112 as well as the rotor 110 rotates during operation of the engine, but the eccentric 132 remains stationary. The powershaft 126 is firmly attached through intermediate members to the outer body 112 so that the powershaft 126 is driven directly by rotation of the outer body 112. During operation there is relative rotation between the rotor 11% and outer body 112, and it is this relative rotation which again creates the variable volume working chambers 125 between the outer peripheral surfaces 142 of the rotor and the inner surfaces 124 of the outer body 112.

As in the first described embodiment, the outer body 112 comprises two end walls 118 and 120 and a peripheral wall 122 interconnecting the end walls. The inner surface contour 124 of the peripheral wall 122 is again in the form of a two-lobed epitrochoid. The rotor 110 also takes virtually the same shape as in the earlier embodiment. As distinguished from the earlier embodiment, however, the outer body 112 of the present embodiment is rotatably supported within a casing 109 by means of antifriction bearings 128 and 130. A stationary eccentric stub 131 is rigidly connected to the casing 109 and also includes a stationary disc 164, which corresponds to the disc 64 of the earlier embodiment, and the eccentric proper 132 is mounted on the stationary disc 164. The stationary eccentric 132 is tubular and, as embodied, comprises two separate parts which are fixed relative to each other through their mutual attachment to the stationary disc 164. Each part of the eccentric 132 is respectively supported on two cylindrical axially directed extensions 133 and 135 of the end walls 120 and 118 respectively of the outer body 112 by means of bearings 13-7 and 139. Rotor 110 in turn is rotatably mounted on the eccentric .132 by means of bearings 134 and 1 36.

As embodied, the rotor 111 has a multi-part construction and the internally toothed gear 150 is secured to the rotor at a point between the end faces 121 and 123 of the rotor instead of at one of the end faces as in the earlier embodiment. Also, the external gear or pinion 154 is carried at the inner end of the cylindrical end wall extension 133 instead of being located immediately adjacent to the end wall 20 to which the end wall extension 133 is secured.

,7 In both embodiments, the gearing serves to positively register or index the position of the rotor relative to the outer body as the rotor rotates relative to the outer body; this positive indexing of the rotor with respect to the outor body relieves the load of positively positioning the rotor from the apex seal means 40* and 140. As in the earlier embodiment, in the present embodiment the ratio between the rotor gear 151) and the external gear 154 which is fixed relative to the outer body 112 is a ratio of 3:2. Accordingly, for each complete revolution of the rotor relative to the outer body 112, or for the completion of one cycle by one chamber, the outer body 112 and with it the powershaft 26, which is rigidly attached to the cylindrical end wall extension 133, will complete three revolutions. The intake passage 144 for fresh gases and the exhaust passage 146 for burnt gases may be see-n in FIG. 6.

In the embodiment of FIGS. 5 and 6 the rotating outer body 112 as well as the rotor 111} is provided with a cooling fluid circuit. The cooling fluid is supplied to the rotary mechanism through an inlet passage 16!] in the stationary eccentric stub 131 and flows into an annular chamber 151 from which it flows through passages 153, 155, and 157 in the end wall 118, the peripheral wall 122, and the end wall respectively of the outer body 112; finally the cooling fluid flows into the cylindrical end wall extension 133. At this point a portion of the cooling fluid leaves the engine through the outlet passage 159 for recirculation through a cooling radiator (not shown) and then back to the supply or inlet passage 160.

At least a portion of the cooling fluid as it leaves the end wall 121} is directed into a passage 161 in the cylindrical end wall extension 133. This latter portion of the cooling fluid flows (as shown by the arrows in FIG. 5) from the inner end of the end wall extension 133 radially outwardly between the inner end of the end wall extension 133 and the stationary disc 164, through suitable passages between the disc 164 and the eccentric 132, and then into the cavity 158 inside the rotor 110.

The stationary disc 164 has a plurality of spaced radially-extending passages 168 radiating from the outer body axis 116 and opening into the rotor cavity 158 at the periphery of the disc as may best be seen in FIG. 6. At their radially inner ends the stationary radial passages 168 communicate with axially extending outlet passages 169 in the stationary eccentric stub 131. The cooling fluid Within the rotor cavity 158 forms a ring at the radially outer surface of the cavity as a result of the centrifugal forces acting on the fluid. When the radial depth of this ring of fluid becomes great enough to cover the outer ends of one or more of the stationary radial passages 168, the centrifugally generated pressure acting on the fluid will be sufficient to force the fluid radially inward through the passages 168. In this manner the passages 16% act as a pump to withdraw excess fluid from the rotor cavity 158 out through the outlet passages 169 for recirculation through a cooling radiator (not shown) from which it may be recirculated back to the supply or inlet passage along with the fluid that is withdrawn from the outlet 159 on the opposite side of the mechanism.

The stationary radial passages 168 extend into the rotor 110 preferably at least to a point radially outward of the rotor bearings 134 and 136 on the eccentric 132 and also radially outward of the teeth of the gears 154 and 150. With this arrangement neither the gears nor the bearings can run immersed in the cooling fluid and churning losses are thereby avoided. Also, the stationary radial passages 168 may advantageously have their radially outer ends inclined so that they are directed into the rotating ring of cooling fluid to facilitate the entrance of the fluid into the passages and to enhance the pumping effect by the 9 centrifugal force on the fluid; and preferably the radial passages 168 may be spiral-shaped.

The cooling fluid used in the instant invention preferably also has lubricating properties. A low viscosity lubricant, such as diesel oil, works well. The present invention thus makes possible the use of a single fluid to accomplish tw-o vital functions of any rotary mechanism or engine: cooling and lubrication. The rotary mechanism may be constructed so that the bearings for the rotor, outer body, and shaft and the gears between the rotor and outer body can all be lubricated by the same fluid which is used to cool the mechanism.

In operation it is apparent that the instant invention offers many advantages .and achieves a number of beneficial results. A large volume of cooling fluid can be circulated directly to the hottest portions of the rotor without any need for an auxiliary pump within the rotor. The invention provides a cooling circuit which utilizes the centrifugal force which is ever present when the mechanism is in operation to provide the pumping force for circulating the cooling fluid within the rotor. An additional advantage of the present invention is that the volume of cooling fluid within the rotor is automatically kept at a level which prevents the bearings and gears from running immersed in cooling fluid. Further, the present invention teaches how one fluid may be used to perform the two functions of cooling and lubrication for the mechanism.

This invention in its broad aspect is not limited to the specific mechanism-s shown and described, but also includes within the scope of the accompanying claims any departures made from such mechanisms which do not depart from the principles of the invention and which do not sacrifice its chief advantages.

What is claimed is:

1. A rotary mechanism for fluid motors, rotary fluid pumps, rotary combustion engines or the like, comprising an outer body having a multi-lobed cavity coaxial therewith, a shaft member having an eccentric portion disposed within said cavity and having an axis parallel to the cavity axis and eccentric thereto, a hollow rotor mounted on said eccentric and disposed within the cavity for rotation relative to the cavity and to the eccentric portion and having a plurality of circumferentially-spaced apex portions having sealing cooperation with the peripheral wall of the cavity to form a plurality of working chambers between the rotor :and the outer body that contain a working fluid and that vary in volume upon relative rotation between the rotor and the outer body, the rotor being radially symmetrical about its axis and having one more apex portion than the cavity has lobes, a cooling system comprising an inlet passage substantially parallel to the axis of the cavity for supplying a cooling liquid rto the rotary mechanism, a second passage communicating with the inlet passage for supplying the cooling liquid to the hollow interior of the rotor, the cooling liquid being carried by centrifugal force to the radially outer surface of the hollow interior of the rotor during rotor rotation, a stationary member extending radi- 10 ally outwardly from the axis of the outer body cavity into the hollow interior of the rotor and having a radius smaller than the radius of the hollow interior of the rotor and having a radial passage open at its periphery, an outlet passage substantially parallel to the axis of the cavity and communicating with the radially inner end of the radial passage, the radial passage being at least intermittently immersed in the cooling liquid distributed by centrifugal force around the radially outer surface of the hollow interior of the rotor, the cooling liquid being forced by centrifugally generated pressure radially inward through the radial passage and into the outlet passage, whereby the cooling liquid is continuously introduced into and removed from the hollow interior of the rotor.

2. The invention as defined in claim 1, including gearing between the outer body and the rotor, and bearing surfaces between the rotor and the eccentric portion of the shaft member, the peripheral end of the radial passage being disposed radially outward of the gearing and bearing surfaces 3. The invention as defined in claim 1, in which the peripheral end of the radial passage is inclined against the direction of rotation of the cooling liquid within the interior of the hollow rotor.

4. The invention as defined in claim 1, in which the stationary member is a disc.

5. The invention as defined in claim 4, in which the disc includes a hub portion having an externally toothed gear, and in which the rotor includes an internally toothed gear in mesh with the externally toothed gear.

6. The invention as defined in claim 1, in which the cooling liquid upon introduction into the rotary mechanism passes successively in a cooling circuit from the outer body to the rotor.

7. The invention as defined in claim 1, in which the cooling liquid is a lubricating oil.

References Cited in the file of this patent UNITED STATES PATENTS 810,975 Petersen Jan. 30, 1906 990,742 Jacobs Apr. 25, 1911 1,228,806 Morris June 5, 1917 1,287,268 Edwards Dec. 10, 1918 1,617,863 Planche Feb. 15, 1927 2,136,117 Nichols Nov. 8, 1938 2,289,440 Kug-el July 14, 1942 2,583,633 Cronin Ian. 29, 1952 2,633,327 McDowell Mar. 31, 1953 2,680,007 Arbuckle June 1, 1954 2,823,849 Muller Feb. 18, 1958 2,956,554 Froede et a1 Oct. 18, 1960 2,974,602 Lock Mar. 14, 1961 2,988,065 Wankel et al. June 13, 1961 3,004,495 Macklis Oct. 17, 1961 FOREIGN PATENTS 541,448 Italy Mar. 29, 1956 1,022,845 Germany Jan. 16, 1958 

1.A ROTARY MECHANISM FOR FLUID MOTORS, ROTARY FLUID PUMPS, ROTARY COMBUSTION ENGINES OR THE LIKE, COMPRISING AN OUTER BODY HAVING A MULTI-LOBED CAVITY COAXIAL THEREWITH, A SHAFT MEMBER HAVING AN ECCENTRIC PORTION DISPOSED WITHIN SAID CAVITY AND HAVING AN AXIS PARALLEL TO THE CAVITY AXIS AND ECCENTRIC THERETO, A HOLLOW ROTOR MOUNTED ON SAID ECCENTRIC AND DISPOSED WITHIN THE CAVITY FOR ROTATION RELATIVE TO THE CAVITY AND TO THE ECCENTRIC PORTION AND HAVING A PLURALITY OF CIRCUMFERENTIALLY-SPACED APEX PORTIONS HAVING SEALING COOPERATION WITH THE PERIPHERAL WALL OF THE CAVITY TO FORM A PLURALITY OF WORKING CHAMBERS BETWEEN THE ROTOR AND THE OUTER BODY THAT CONTAIN A WORKING FLUID AND THAT VARY IN VOLUME UPON RELATIVE ROTATION BETWEEN THE ROTOR AND THE OUTER BODY, THE ROTOR BEING RADIALLY SYMMETRICAL ABOUT ITS AXIS AND HAVING ONE MORE APEX PORTION THAN THE CAVITY HAS LOBES, A COOLING SYSTEM COMPRISING AN INLET PASSAGE SUBSTANTIALLY PARALLEL TO THE AXIS OF THE CAVITY FOR SUPPLYING A COOLING LIQUID TO THE ROTARY MECHANISM, A SECOND PASSAGE COMMUNICATING WITH THE INLET PASSAGE FOR SUPPLYING THE COOLING LIQUID TO THE HOLLOW INTERIOR OF THE ROTOR, THE COOLING LIQUID BEING CARRIED BY CENTRIFUGAL FORCE TO THE RADIALLY OUTER SURFACE OF THE HOLLOW INTERIOR OF THE ROTOR DURING ROTOR ROTATION, A STATIONARY MEMBER EXTENDING RADIALLY OUTWARDLY FROM THE AXIS OF THE OUTER BODY CAVITY INTO THE HOLLOW INTERIOR OF THE ROTOR AND HAVING A RADIUS SMALLER THAN THE RADIUS OF THE HOLLOW INTERIOR OF THE ROTOR AND HAVING A RADIAL PASSAGE OPEN AT ITS PERIPHERY, AN OUTLET PASSAGE SUBSTANTIALLY PARALLEL TO THE AXIS OF THE CAVITY AND COMMUNICATING WITH THE RADIALLY INNER END OF THE RADIAL PASSAGE, THE RADIAL PASSAGE BEING AT LEAST INTERMITTENTLY IMMERSED IN THE COOLING LIQUID DISTRIBUTED BY CENTRIFUGAL FORCED AROUND THE RADIALLY OUTER SURFACE OF THE HOLLOW INTERIOR OF THE ROTOR, THE COOLING LIQUID BEING FORCED BY CENTRIFUGALLY GENERATED PRESSURE RADIALLY INWARD THROUGH THE RADIAL PASSAGE AND INTO THE OUTLET PASSAGE, WHEREBY THE COOLING LIQUID IS CONTINUOUSLY INTRODUCED INTO AND REMOVED FROM THE HOLLOW INTERIOR OF THE ROTOR. 